<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style type="text/css">
	.red{
		width: 300px;
		height: 300px;
		background: red;
		display: none;
	}
	.green{
		width: 300px;
		height: 300px;
		background: green;
	}
	</style>
</head>
<body>
	<div class="red"></div>
	<div class="green"></div>

</body>
</html>